1. Field of the Invention
The invention relates to an electronic device, a liquid crystal display module, a backlight unit and a front frame thereof. In particular, the invention relates to the electronic device, the liquid crystal display module, the backlight unit and the front frame thereof with improved assembly precision and reduced costs.
2. Description of the Related Art
Referring to FIG. 1A, FIG. 1A is an exploded view from the front angle of a conventional liquid crystal display module 10. As shown in FIG. 1A, the conventional liquid crystal display module 10 comprises a front cover 12, a panel 14 and a backlight unit 16, wherein the panel 14 and the backlight unit 16 respectively comprise flexible circuit boards 147, 167.
Referring to FIG. 1B, FIG. 1B is a schematic view from the back angle of the liquid crystal display module 10 in FIG. 1A. As shown in FIG. 1B, in the assembled backlight unit 16, the flexible circuit board 167 of the backlight unit 16 is electrically connected to the flexible circuit board 147 of the panel 14. Additionally, the liquid crystal display module 10 electrically connects with an external control circuit (not shown) through the flexible circuit board 147.
Referring to FIG. 2A and FIG. 2B simultaneously, FIG. 2A is an exploded view from the front angle of the conventional backlight unit 16, and FIG. 2B is an exploded view from the back angle of the backlight unit 16 in FIG. 2A. As shown in FIG. 2A and FIG. 2B, the backlight unit 16 is assembled by stacking an upper cover 161, a front frame 162, a plurality of optical films 163, a light guide plate 164, a reflective plate 165 and a back frame 166 in sequence. Usually, the front frame 162 is a plastic frame and the back frame 166 is an iron frame.
The backlight unit 16 utilizes a point light source 168 to provide a light beam. The point light source 168 is a light emitting diode disposed on the flexible circuit board 167. Referring to FIG. 3 simultaneously with FIG. 2A and FIG. 2B, FIG. 3 is a plan view of the flexible circuit board 167 in FIG. 2B. As shown in FIG. 3, the point light source 168 is disposed on an end of the flexible circuit board 167, and the contacts 1674 are disposed on the other end of the flexible circuit board 167. Electricity is inputted from the contacts 1674, and through a conductive line 1672, to the point light source 168.
During operation, the point light source 168 generates a light beam. The light beam is guided by the light guide plate 164 to change directions, be uniformed by the optical films 163, and then be emitted out of the backlight unit 16. The reflective plate 165 reflects light beams which leak out from under the light guide plate 164 back toward the light guide plate 164, for energy efficiency.
However, during the assembly of the conventional backlight unit 16, the flexible circuit board 167 might be stretched so that the point light source 168 is shifted, causing non-uniform illumination of the backlight unit 16.